CN104276803A - Shrinkage-free high-strength pouring mortar material and preparation method thereof - Google Patents
Shrinkage-free high-strength pouring mortar material and preparation method thereof Download PDFInfo
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Abstract
The invention belongs to the field of research and application of pouring materials, and provides a shrinkage-free high-strength pouring mortar material and a preparation method thereof aiming at overcoming the defects of short mixture construction time, instability in mixture placeability, poor volume stability and the like of the traditional grouting material. The shrinkage-free high-strength pouring mortar material is prepared from silicate cement, alumina cement, dihydrate gypsum, an inhibiting agent, a polycarboxylic acid high-efficiency water reducing agent and the like according to a certain proportion. The shrinkage-free high-strength pouring mortar material provided by the invention improves the construction property of a pouring mortar material and ensures that a pouring mortar mixture is stable in property and has good adjustable construction property and weakly expansive property and excellent cracking-resistant property. According to the preparation method, the application and use fields of a product are extended by dynamically adjusting the construction property of the material mixture, and the product can be applied to the fields of concrete structure reconstruction, strengthening, prestressed duct grouting, anchor sealing, road repair, tunnel plugging and the like on the basis of the traditional mechanical equipment installation, strengthening and repair project.
Description
Technical field
The invention belongs to pouring material research Application Areas, be specifically related to high-strength pouring mortar material of a kind of ungauged regions and preparation method thereof.
Background technology
Pouring mortar slurry is for base material gathers materials with inorganic or organic gel gel material, be composited with the fine aggregate of specific grating, superplasticizer, Application Areas is mainly mechanical equipment installation, structural strengthening, renovation reinforced fast, the fields such as special operation condition application and construction, there is very high hour intensity, later strength is high, do not shrink, the ultimate compression strength of 20-40Mpa within 2 hours, can be obtained, High anti bending strength.28d ultimate compression strength reaches as high as more than 100Mpa, have large fluidity, self-compacting simultaneously, do not need to vibrate, smear pressure, speed of application waits feature performance benefit soon, there is the shortcomings such as mixture workability is unstable, volume stability is poor in the injection material of current use, affects construction quality and pouring quality.Therefore improving the workability of pouring mortar material, ensure the stable performance of pouring mortar mixture, make it have the cracking resistance of good adjustable workability and microdilatancy performance and excellence and high-strength performance, is the problem that current injection material needs to solve.
Summary of the invention
The present invention in order to solve current existing injection material there is mixture can unstable, the shortcoming such as volume stability is poor of engineering time short, mixture workability, provide high-strength pouring mortar material of a kind of ungauged regions and preparation method thereof.
The present invention is realized by following technical scheme: the high-strength pouring mortar material of a kind of ungauged regions, and the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 12-20%; High-alumina cement 70-80%; Dihydrate gypsum 5-10%; Retardant 0.2-0.5%; High-efficiency water-reducing agent of poly-carboxylic acid 0.8-1.5%; Polypropylene fibre 0.05-0.08%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:0.8-1; Retardant, water reducer and polypropylene fibre are with gelling material mass percent, and aggregate adopts grating quartz sand to be configured.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.Described gelling material refers to the quality summation of silicate cement, high-alumina cement and dihydrate gypsum.
Prepare a method for the high-strength pouring mortar material of ungauged regions, concrete steps are as follows:
Preparation according to (1) raw material and utensil: before preparation by raw material and utensil used temperature 23 ± 2 DEG C, relative humidity 50% ~ 90% time placement >=24h; (2) each raw material is taken respectively by massfraction, pour planetary adjustable speed stirrer into, be that 0.09-0.19 adds water by ratio of water to material, at the uniform velocity add water after starting 250r/min low rate mixing, to add after 90% of total Water 250r/min low rate mixing 90s again, then add residue water after 500r/min rapid stirring 60s, last 250r/min low rate mixing 1min, stir and obtain the high-strength pouring mortar material of ungauged regions.
According to the corresponding relation of material proportion to mortar performance index, adopt ternary phase diagrams method, with mortar performance index request with to reply material component ratio-dependent ternary gelling material optimum proportion, silicate cement cement content 12 ~ 20%, high-alumina cement 60 ~ 80%, dihydrate gypsum 5 ~ 10%, auxiliary employing high-efficiency water-reducing agent of poly-carboxylic acid and retardant, retardant adopts boric acid+Sunmorl N 60S compound, compositely proportional is 1:0.8-1, volume 0.2-0.5% dynamic conditioning, improve slurry viscosity, degree of mobilization gradual loss and adjustable controlled for time of coagulation to slurry, effective control initial flow degree and time of coagulation, meet the workability requirement of different application field.
It is toughner that the present invention increases high molecular polymer, adopt the quartz sand of reasonable fraction as high strength aggregate, be aided with upper flow regime, microdilatancy, anti-segregation, the admixture such as crack-resistant, improve the workability of pouring mortar material, ensure the stable performance of pouring mortar mixture.Different according to Application Areas, the workability of mixture requires different, employing binary regression, ternary phase diagrams method adjust material component proportioning, the application of expanding product uses field, make it have and be adapted to repairing, track is filled, support grouting, is especially applicable to High-speed Railway Bridges beam support or track filling etc.
Compared with prior art, the present invention improves workability, the stable performance of guarantee pouring mortar mixture of pouring mortar material, makes it have good adjustable workability and the anti-cracking performance of microdilatancy performance and excellence.The workability of dynamic conditioning material mixture, the application of expanding product uses field, install in conventional mechanical devices on the basis of reinforcing and repairing engineering, can be applicable to the fields such as concrete structure transformation, reinforcing and prestressed pore passage grouting, sealing off and covering anchorage, road rapid repair, tunnel leak stopping.
Embodiment
Embodiment 1: the high-strength pouring mortar material of a kind of ungauged regions, the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 12%; High-alumina cement 80%; Dihydrate gypsum 8%; High-efficiency water-reducing agent of poly-carboxylic acid, retardant and polypropylene fibre by gelling material mass ratio are: retardant 0.5%; High-efficiency water-reducing agent of poly-carboxylic acid 1%; Polypropylene fibre 0.08%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:1.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.
Prepare a method for the high-strength pouring mortar material of ungauged regions, concrete steps are as follows: the preparation of (1) raw material and utensil: before preparation by raw material and utensil used temperature 23 ± 2 DEG C, relative humidity 50% ~ 90% time placement >=24h; (2) each raw material is taken respectively by massfraction, pour planetary adjustable speed stirrer into, be that 0.09-0.19 adds water by ratio of water to material, at the uniform velocity add water after starting 250r/min low rate mixing, add the rear low rate mixing 90s of total Water 90%, and then 500r/min adds residue water after stirring 60s fast, finally 250r/min stirs 1min at a slow speed, stirs and obtains the high-strength pouring mortar material of ungauged regions.
The high-strength pouring mortar material of the ungauged regions prepared, time of coagulation, test was undertaken by the regulation of Section 4 in GB/T 50080-2002; Slump test is undertaken by the regulation in JC/T 986-2005; Bleeding rate test by GB/T 50080-2002 5.1 regulation carry out; Ultimate compression strength and folding strength are according to GB/T 17671-1999; Strength of cement mortar inspection ISO method is carried out: pour the mortar material mixed into die trial, do not vibrate, and 2h compression strength test should form removal in 2min before the test, should be carried out in accordance with regulations strength trial immediately after form removal; Young's modulus carries out according to JGJ 70-90 building mortar basic performance tests method chapter 8 static(al) pressurized elasticity modulus test method; Rate of expansion is carried out with reference to free swell test method in JC/T 453-1992 self-stressing cement physical testing method: the test test specimen demoulding of mortar expansion rate and maintenance regulation: mortar stirs and is molded over form removal after maintenance 24h ± 1h under standard bar, its initial length of rapid test, then maintenance surveys its length to 28d; Shrinking percentage is carried out with reference to free swell test method in JC/T 453-1992 self-stressing cement physical testing method, and the form removal after maintenance 24h ± 1h at the standard conditions of hardenite test specimen, its initial length of test, then carries out maintenance as standard drying shrinkage room rapidly.
Admixture specification is L=4-6mm, the polypropylene fibre 0.05-0.08% of d=0.06-0.08mm, improve mixture segregation and bleeding, aggregate is uniformly distributed, formed and there is the good homogeneous bulk of water retention property, reduce thermal cracking and long-term shrinkage crack, stop the expansion of cement matrix native defect (microfracture) also effectively to delay the appearance in new crack, after slurry is hardened, there is good resistance to cleavage.This material is suitable for concrete structure transformation.
Different according to construction technique, to employing directly perfusion and adopt that cement mortar rate is carried out in the construction of pressure injection technology mode, grading of aggregate, degree of mobilization carry out dynamic conditioning, choose 4 kinds of artificial grating quartz sands as the corresponding cement mortar rate of filler aggregate grating for proportioning application as table 1:
Using standard: " Test method for strength of hydraulic cement mortar " (ISO method) GB/T 17671-1999; " Standard for test methods of properties of ordinary concrete mixture standard " GB/T 50080-2002; " self-stressing cement physical testing method " JC/T 453-1992; " planetary cement mortar mixer " JC/T 681-2005; " cement-based grouting material " JC/T 986-2005; " concrete mixing water supply standard " JGJ 63-1989; " building mortar basic performance tests method " JGJ 70-90.
Embodiment 2: the high-strength pouring mortar material of a kind of ungauged regions, the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement 14%, high-alumina cement 78%, gypsum 8%, high-efficiency water-reducing agent of poly-carboxylic acid, retardant and polypropylene fibre with glue material amount for radix is calculated as: high-efficiency water-reducing agent of poly-carboxylic acid 1%, retardant 0.5%, polypropylene fibre 0.08%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:0.8.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.Preparation method and using standard are with preparation method and application's specification described in embodiment 1.
Prepared ungauged regions high-strength pouring mortar material fundamental property Testing index is table 2, result can draw: improve the workability of pouring mortar material, ensure the stable performance of pouring mortar mixture, make it have good adjustable workability and the anti-cracking performance of microdilatancy performance and excellence.The workability of dynamic conditioning material mixture, the application of expanding product uses field, installs on the basis of reinforcing and repairing engineering in conventional mechanical devices, can be applicable to concrete structure transformation, reinforces and prestressed pore passage grouting.
Table 2: fundamental property index
Embodiment 3: the high-strength pouring mortar material of a kind of ungauged regions, the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 20%; High-alumina cement 70%; Dihydrate gypsum 10%; High-efficiency water-reducing agent of poly-carboxylic acid, retardant and polypropylene fibre by glue material mass ratio are: retardant 0.2%; High-efficiency water-reducing agent of poly-carboxylic acid 1%, polypropylene fibre 0.05%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:0.8.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.Preparation method and using standard are with preparation method and application's specification described in embodiment 1.This material is suitable for road rapid repair, tunnel leak stopping.
Embodiment 4: the high-strength pouring mortar material of a kind of ungauged regions, the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 18%; High-alumina cement 77%; Dihydrate gypsum 5%; High-efficiency water-reducing agent of poly-carboxylic acid, retardant and polypropylene fibre by glue material mass ratio are: retardant 0.35%; High-efficiency water-reducing agent of poly-carboxylic acid 0.8%; Polypropylene fibre 0.05%; Wherein said retardant is boric acid and Sunmorl N 60S 1:0.9 ratio compound.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.Preparation method and using standard are with preparation method and application's specification described in embodiment 1.This material is suitable for High-speed Railway Bridges beam support or track is filled.
Embodiment 5: the high-strength pouring mortar material of a kind of ungauged regions, the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 20%; High-alumina cement 70%; Dihydrate gypsum 10%; High-efficiency water-reducing agent of poly-carboxylic acid, retardant and polypropylene fibre by glue material mass ratio are: retardant 0.43%; High-efficiency water-reducing agent of poly-carboxylic acid 1.5%; Polypropylene fibre 0.07%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:0.8.Described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.Preparation method and using standard are with preparation method and application's specification described in embodiment 1.This material is suitable for basis perfusion, sealing off and covering anchorage etc.
Claims (3)
1. the high-strength pouring mortar material of ungauged regions, is characterized in that: the mass percent that feed composition and each component account for raw material total amount is as follows: silicate cement: 12-20%; High-alumina cement 70-80%; Dihydrate gypsum 5-10%; Retardant 0.2-0.5%; High-efficiency water-reducing agent of poly-carboxylic acid 0.8-1.5%; Polypropylene fibre 0.05-0.08%; Wherein said retardant is the ratio compound of boric acid and Sunmorl N 60S 1:0.8-1; Retardant, water reducer and polypropylene fibre are with gelling material mass percent, and aggregate adopts grating quartz sand to be configured.
2. a kind of ungauged regions high strength pouring mortar material according to claim 1, is characterized in that: described polypropylene fibre specification: long is 4-6mm, and diameter is 0.06-0.08mm.
3. prepare the method for the high-strength pouring mortar material of ungauged regions according to claim 1 for one kind, it is characterized in that concrete steps are as follows: the preparation of (1) raw material and utensil: before preparation by raw material and utensil used temperature 23 ± 2 DEG C, relative humidity 50% ~ 90% time placement >=24h; (2) each raw material is taken respectively by massfraction, pour planetary adjustable speed stirrer into, be that 0.09-0.19 adds water according to water and raw material ratio, at the uniform velocity add water after starting 250r/min low rate mixing, to add after 90% of total Water 250r/min low rate mixing 90s again, then add residue water after 500 r/min rapid stirring 60s, last 250r/min low rate mixing 1min, stir and obtain the high-strength pouring mortar material of ungauged regions.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108101474A (en) * | 2018-01-15 | 2018-06-01 | 北京首发公路养护工程有限公司 | Anti- isolation road rapid repair material of low temperature contracting Self-leveling and preparation method thereof |
| CN108137425A (en) * | 2015-10-20 | 2018-06-08 | 喜利得股份公司 | Load value is increased in anchoring is applied based on the bicomponent mortar system that alumina cement includes calcium sulfate and reduces the purposes shunk |
| CN108218359A (en) * | 2018-01-31 | 2018-06-29 | 中铁二局第四工程有限公司 | A kind of cement base high-performance microdilatancy filling and injecting slurry material |
| CN110282945A (en) * | 2019-08-13 | 2019-09-27 | 吉林重通成飞新材料股份公司 | A kind of gypsum based composite, preparation method and plaster formulation part |
| CN110467397A (en) * | 2019-08-31 | 2019-11-19 | 中国水利水电第五工程局有限公司 | A kind of pre contract mortar and preparation method thereof |
| CN110590302A (en) * | 2019-10-10 | 2019-12-20 | 兰溪市昆仑工程材料有限公司 | Grouting plugging agent and preparation method thereof |
| CN111003978A (en) * | 2020-01-08 | 2020-04-14 | 广西建宏水泥制品有限公司 | Building secondary structure grouting mortar |
| CN116283080A (en) * | 2023-01-29 | 2023-06-23 | 山东大学 | Cement stabilizing layer rapid repair material and preparation method and application thereof |
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| CN1800291A (en) * | 2004-12-30 | 2006-07-12 | 同济大学 | Water-proofing material for stopping leak |
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| CN1800291A (en) * | 2004-12-30 | 2006-07-12 | 同济大学 | Water-proofing material for stopping leak |
| CN103864393A (en) * | 2014-03-20 | 2014-06-18 | 上海泛欧建筑材料有限公司 | Special reinforcing mortar for wharf concrete structure |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108137425A (en) * | 2015-10-20 | 2018-06-08 | 喜利得股份公司 | Load value is increased in anchoring is applied based on the bicomponent mortar system that alumina cement includes calcium sulfate and reduces the purposes shunk |
| US11214526B2 (en) | 2015-10-20 | 2022-01-04 | Hilti Aktiengesellschaft | Use of calcium sulfate in an inorganic mortar system based on aluminous cement to increase load values |
| CN108101474A (en) * | 2018-01-15 | 2018-06-01 | 北京首发公路养护工程有限公司 | Anti- isolation road rapid repair material of low temperature contracting Self-leveling and preparation method thereof |
| CN108218359A (en) * | 2018-01-31 | 2018-06-29 | 中铁二局第四工程有限公司 | A kind of cement base high-performance microdilatancy filling and injecting slurry material |
| CN110282945A (en) * | 2019-08-13 | 2019-09-27 | 吉林重通成飞新材料股份公司 | A kind of gypsum based composite, preparation method and plaster formulation part |
| CN110467397A (en) * | 2019-08-31 | 2019-11-19 | 中国水利水电第五工程局有限公司 | A kind of pre contract mortar and preparation method thereof |
| CN110590302A (en) * | 2019-10-10 | 2019-12-20 | 兰溪市昆仑工程材料有限公司 | Grouting plugging agent and preparation method thereof |
| CN111003978A (en) * | 2020-01-08 | 2020-04-14 | 广西建宏水泥制品有限公司 | Building secondary structure grouting mortar |
| CN116283080A (en) * | 2023-01-29 | 2023-06-23 | 山东大学 | Cement stabilizing layer rapid repair material and preparation method and application thereof |
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Inventor after: Duan Fengtao Inventor after: Yi Dan Inventor after: Bie Yonghui Inventor after: Wang Tao Inventor after: Ma Jing Inventor after: Chen Chunyu Inventor after: Dou Wei Inventor after: Xu Liangliang Inventor after: Liang Lijiu Inventor after: Hao Yushuai Inventor after: Cheng Zhenggang Inventor before: Bie Yonghui Inventor before: Wang Tao Inventor before: Yi Dan Inventor before: Chen Chunyu Inventor before: Duan Fengtao Inventor before: Dou Wei Inventor before: Xu Liangliang Inventor before: Liang Lijiu Inventor before: Ma Jing Inventor before: Hao Yushuai |
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Effective date of registration: 20191224 Address after: 030001 No. 269, Yingze Avenue, Yingze District, Shanxi, Taiyuan Patentee after: Shanxi Tiansheng Surveying and Mapping Engineering Co., Ltd. Address before: 030006 No. 5 Xuefu street, Shanxi, Taiyuan Co-patentee before: China Railway Third Engineering Co., Ltd. Patentee before: Shanxi Sanjiang Engineering Detection Co., Ltd. |